Chondroitin-4-sulfate polysaccharide

The chromic acid oxidations of HCO2H, L-methionine, chondroitin-4-sulfate polysaccharide, aniline and A-methylaniline, and syringic acid and 4-methoxycinnamic acid are reported. The oxidation of HCO2H is studied both in the presence and in the absence of 2,2 -bipyridine (bipy) as a catalyst in aqueous acidic micellar media. In the absence of bipy, the reactive HCr04 species forms an ester with HCO2H which disproportion-ates in the rate-determining step through 3e transfer. The Cr(VI)-bipy complex, the... 

Hyaluronic Acid and Chondroitin Sulfate (Polysaccharides of Human Origin) ... 

Metabolic Functions. Manganese is essential for normal body stmcture, reproduction, normal functioning of the central nervous system, and activation of numerous enzymes (126). Synthesis of the mucopolysaccharide chondroitin sulfate involves a series of reactions where manganese is required in at least five steps (127). These reactions are responsible for formation of polysaccharides and linkage between the polysaccharide and proteins that form... 

Dermatan sulfate, also termed chondroitin sulfate B, a related glycosaminoglycan constituent of connective tissue, was known to be composed of galactosamine and a uronic acid, originally believed to be glucuronic acid but then claimed to be iduronic acid based largely on color reactions and paper chromatography. However, the d or L-enantiomer status of the latter monosaccharide was not clear. Jeanloz and Stoffyn unequivocally characterized the monosaccharide as L-iduronic acid by consecutive desulfation, reduction, and hydrolysis of the polysaccharide, followed by isolation of the crystalline 2,3,4-tri-0-acetyl-l,6-anhydro-/ -L-idopyranose, which was shown to be identical to an authentic specimen synthesized from 1,2-0-isopropylidene-/ -L-idofuranose.34... 

Such enzymatic catalyzed polycondensations have allowed the synthesis of a number of natural polysaccharides, but has also allowed the production of nonnatural polysaccharides such as cellulose-xylan hybrids and functionalized hyaluronan, chondroitin sulfate, and chondroitin. Such work illustrates the ever-narrowing bridge between natural and synthetic polymers and polymer syntheses. 

The second polysaccharide present in cartilage proteogylcan is keratan sulfate. It is generally found in shorter chains than chondroitin sulfate with an average molecular weight of about 20,000 Da. It is also found in the cornea of the eye. 

Nishi has found that chondroitin sulfate A and C are more effective in the resolution of basic drugs than dextran or dextrin and even dextran sulfate because of additional ionic interactions with sulfate or carboxylic groups. The small ionic character of chondroitin sulfate C leads to large enantiose-lectivity under acidic conditions, whereas heparin was not so effective. Using neutral polysaccharides, only hydrophobic interactions and hydrogen bonding may occur (117). 

Gargiulo, V., Lanzetta, R., Parrilli, M., and De Castrol, C. (2009). Structural analysis of chondroitin sulfate from Scyliorhinus canicula A useful source of this polysaccharide. Glycobiology 19,1485-1491. 

Model building in the computer is used to analyze the conformational effects of steric interactions between atoms of the polymer skeleton for x-carrageenan, t-carrageenan, A-carrageenan, agar, chondroltin, chondroitin sulfates, dermatan sulfate, keratan sulfate, hyaluronic acid, and related polysaccharides. Over 99% of the conformations are thus excluded and virtually all of the remainder for each polysaccharide lie close together. Predictions are also made from disaccharide crystal structures and checked against experimental results. 

The organic substances of the biocrystalline layer include primarily protein-polysaccharide complexes while the contents of water and lipids are low376. Polysaccharides composed of glucosamine, galactosamine, mannose and fucose have been detected. Also chondroitin-sulfate-A and dermatan sulfate have been found368. ... 

The attached polymers undergo enzyme-catalyzed chemical alteration. In dermatan most of the glucu-ronate residues found in chondroitin have been epimer-ized to iduronate and sulfate groups in ester linkages have been added. Chondroitin sulfate is especially abundant in cartilage dermatan sulfate is concentrated in skin. Heparan sulfates are more heterogeneous than the other polymers of this group and have been described as "the most complex polysaccharides on the surface of mammalian cells."110... 

Proteoglycans bind to a variety of different proteins and polysaccharides. For example, the large extracellular matrix protein tenascin, which is important to adhesion, cell migration, and proliferation, binds to chondroitin sulfate proteoglycans such as neurocan.225 Syndecan, a transmembrane proteoglycan, carries both chondroitin and heparan sulfate chains, enabling it to interact with a variety of proteins that mediate cell-matrix adhesion.185... 

FIGURE 1 Potential hydrolysis rates of six structurally distinct polysaccharides in seawater (A) and surface sediments (B) from Skagerrak and Svalbard. Pull = pullulan, lam = laminarin, xyl = xylan, fu = fucoidan, ara = arabinogalactan, chon = chondroitin sulfate. Note the differences in scale on the y axes for sediments and for seawater. [Skagerrak data from Arnosti (2000).]... 

Manganese is essential for the synthesis of chondroitin sulfate, a mucopolysaccharide which is an important component of bone cartilage. Manganese is also required to activate enzymes involved in the synthesis of polysaccharides and... 

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